The present invention relates (1) to a throat guard, (2) to a frame for maintaining the throat guard in the desired position in a patient's mouth during a dental procedure, and (3) to the assembled combination of the throat guard and frame device.
In a number of dental procedures, the danger of small articles (e.g. dental tools, teeth, dental appliances or pieces of any of these) slipping into the patient's throat has long been known. A number of published articles reveal this to be a real existing problem with potentially life endangering aspects (e.g. when the object falls into bronchial passages). Corrective surgery to retrieve the object is often required when such accidents occur. And, in any event, the potential malpractice problems created for the doctor involved in such an accident and the mental trauma suffered by the patient under these circumstances are also very real.
In view of these obvious dangers, a number of prior devices have been proposed for preventing passage of small articles into the throat of the dental patient. One type of device that has generally been so considered and employed is a socalled "rubber dam" that is placed over and/or within the mouth of the patient and which is provided with limited openings providing access to a portion of the mouth or jaw in which work is to be done. However, such rubber dams are typically not used in everyday practice because they are difficult and time consuming to apply as well as restrictive to use. It can also give the patient a sense of lost breathing ability if the nasal air passages are or become blocked or restricted for some reason. These and other prior devices have often interfered with the dental surgeon's access to the tooth or to the portion of the jaw needing attention and/or have been uncomfortable for the patients if in place for an extended time.
Some of these prior art devices are depicted, for example, in:
U.S. Pat. No. 590,460--Mehlig
U.S. Pat. No. 1,401,646--Ronn
U.S. Pat. No. 3,406,452--McConville
U.S. Pat. No. 3,772,790--Swan-Gett et al.
U.S. Pat. No. 3,662,466--McConville
U.S. Pat. No. 4,259,067--Nelson
Although Swan-Gett et al. teach a form of rubber dam which includes a bi-valve spring biased structure, they do not in any way suggest an opened spring structure capable of receiving and retaining a disposable strainer element.
Nelson teaches a relatively porous and flexible shield material. It is said to be permeable to saliva and it might presumably therefore also be permeable to air. However, Nelson arranges his shield in a vertical orientation and his bi-valve frame member does not actually extend on the outside of the teeth and jaw but, rather, is disposed inside of the teeth and jaw structure.
The remainder of the above-cited references appear of even less interest although they do appear to be generally relevant to show other prior art approaches to this same problem.
By way of contrast, I have now discovered a novel throat guard and a retention frame therefor which, separately and in combination, offer a substantial improvement over such prior devices. This novel arrangement is simple to use, requires no doctor time (it can be inserted by an assistant), has a high margin of safety, and allows total exposure for operating on all teeth in either arch of the mouth. It can also be constructed so as to be comfortably accommodated by a patient and so as not to substantially interfere with patient breathing through the mouth.
In a presently preferred exemplary embodiment, the throat guard of the present invention includes an air permeable flexible sheet material which is tear resistant when wet and which is shaped to completely occlude the throat passages from the passage of small objects. It includes a rear leaf portion which is folded upwardly and forwardly so as to seal to the hard plate of the mouth by a salivary seal. It is oversized elsewhere so as to extend at its forward and forward side edges over the patient's lower teeth and tongue with the excess resting in the lower muco-buccal fold. A desired section is cut away to provide access to any desired portion of the lower arch. The entire upper arch is automatically unobstructed at all times.
This invention also includes an exemplary embodiment for the separate retaining device which holds the throat guard in place. In the present exemplary embodiment, the retaining device includes a three-element frame which may be made of orthodontic spring wire, with each of the wires shaped so as to comfortably fit between the teeth and cheeks of the patient. Two of the wires form the lower retaining element for the throat guard, while the upper single wire element (which is biased away from the lower two elements) assists in maintaining the lower two elements in place in the patient's mouth. The upper wire element may be made of relatively heavier gauge wire to aid the retention as well as anchorage and mouth forming functions of the frame.
The combination of such a throat guard and retaining frame itself provides a novel and advantageous overall structure in which the component parts cooperate as above suggested to provide an optimum throat protection.
Stated somewhat differently, the exemplary embodiment of this invention comprises a three-element spring frame in combination with a specially shaped mouth/throat guard formed of air permeable material so as to permit breathing therethrough. Nevertheless, the mouth/throat guard provides a "strainer" structure having a mesh of sufficiently small interstices so as to catch foreign objects (e.g., dental tools, pieces of fillings, teeth, etc.) from passing on down the patient's throat. The "strainer" material is tear resistant when wet and one suitable material may be the material that breathing masks are typically made of or material such as the Telfa breathing type of bandage marketed by Colgate-Palmolive Co.
The exemplary three-element spring frame may be made of spring wire such as orthodonic wire normally used by dentists to build teeth braces or the like or it might be stamped from plastic or otherwise formed from other materials. In any event, it is generally shaped like the bi-valve jaw opening. It is dimensioned so as to fit outside the jaw and tooth structure so as to urge the cheeks away from the teeth and gums while also keeping the bottom portion of the exemplary bi-valve arrangement spring biased downwardly toward the bottom of the mouth structure. The bottom portion of the exemplary bi-valve structure actually comprises two closely adjacent elements (preferably spring biased toward one another) through which a disposable strainer element may be inserted. The strainer element is generally shaped to conform to the interior of the mouth surfaces but it includes a generally rounded posterior flap which obstructs the very back part of the throat area behind the teeth so that foreign objects are not permitted to fall down into the throat. Since this material is air permeable, the patient can easily breath through it, if required, thus not evoking a gag reflex. The posterior flap may have a fold pre-formed in it so as to project upwardly and forwardly in the back throat area.
The foregoing and other objects and advantages of my invention will become apparent as consideration is given to the following detailed description of a presently preferred exemplary embodiment taken in conjunction with the accompanying drawings, in which: